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1.
甘肃省黑河流域土地沙漠化的水文学指征初探   总被引:1,自引:0,他引:1  
黑河流域土地沙漠化及水资源合理利用一直是该流域研究的焦点问题。文章首先从土地沙漠化分布范围、种类、面积、沙漠化程度等方面,分析了黑河流域土地沙漠化的现状:土地沙漠化主要发生在流域的中下游地区,尤以额济纳绿洲沙漠化形势严峻;其次,从地表水、地下水之水质、水量方面分析了黑河流域水环境变化的状况:人类不合理的经济活动,导致黑河流域水资源环境恶化,具体表现在地下水、地表水水位下降、水质恶化。在此基础上,从黑河流域地表水及地下水着手,初步提出了黑河流域土地沙漠化的水文学指征体系:其中,地表水主要包括蒸发与蒸腾的消耗、径流和渗漏3个部分;径流部分又分为地表水流经区域及水量变化、干流水量的系列变化以及泥沙沉积3方面;地下水则主要有水质变化及水位的连续变化2方面。  相似文献   

2.
基于ExcelVBA的模糊综合评判地表水水质评价   总被引:1,自引:0,他引:1  
汤信彬 《福建地质》2012,31(1):74-83
地表水水质是地质环境质量评价主因素之一,对永安市小陶镇10组地表水水质数据选用模糊综合评价法,基于Micro Soft office Excel VBA编程进行了综合快速评价。评价结果表明:下游各项污染指标均略高于上游;盆地外围支流的地表水水质均较好,除西学溪锌偏高微超标外,其它均在Ⅱ类水质范围内。实验证明利用VBA完成模糊综合评判方法有效性,并具有可移值性,只须修改少量代码即可完成其它区域的水质评价。  相似文献   

3.
《地下水》2017,(1)
以黄土塬典型干旱半干旱区正宁县为研究对象,将模糊综合评判法引入正宁县地表水水质评价,采用模糊变换原理和最大隶属度原则,构建正宁县区域内地表水水质模糊综合评判模型,对不同河流和水库地表水的水质指标检测数据作出了定量的综合评价。结果表明:该县区域内庵里水库和无日天沟水质达到地表水Ⅱ类水质,嘉峪川河、四郎河、支党河达到Ⅰ类水质;从权重计算结果可以看出,正宁县区域内主要地表水水源庵里水库、嘉峪川河、四郎河、支党河主要污染物为NH3-N、DO;无日天沟主要污染物为CODMn、DO。说明该县区域内主要地表水水源治理和保护情况较好,水源水质均达到Ⅱ类水质以上。但作为人饮重要水源还需要继续加强保护和治理,为该区域城镇居民生活用水安全和社会经济发展提供基础保障。  相似文献   

4.
巴东北部地区地表水的环境化学特征及水质评价   总被引:1,自引:0,他引:1  
对巴东北部地区地表水的环境化学特征进行了初步研究,并且定量分析了此区域的水质.研究表明,该地区地表水属于典型的碳酸盐地表水,元素含量都处于低水平,没有明显的重金属污染,测定7个水样中的元素含量的平均值可以作为巴东北部地区地表水的背景值.  相似文献   

5.
为查明高店子幅地表水和地下水的水化学特征及水环境质量现状,为区域水资源保护与开发提供理论依据,运用数理统计分析、模糊综合评价和灌溉水水质评价方法对研究区地表水和地下水进行了分析与评价。研究结果表明:研究区地表水水化学组分波动较大,地下水水化学组分相对较为稳定。地表水水化学类型主要为重碳酸硫酸-钙镁型水和重碳酸-钙镁型水;地下水水化学类型主要为重碳酸-钙镁型水和重碳酸硫酸-钠钙镁型水。研究区地表水和地下水水力联系密切,水中主要离子组分来自于盐岩、石膏和碳酸盐的风化溶滤,另外还存在阳离子交换作用、蒸发浓缩作用和人类活动的共同影响。饮用水水质评价表明,54.5%的地表水和71.4%的地下水适于饮用或基本适于饮用,地下水水质稍好于地表水水质;灌溉水水质评价表明,研究区地表水和地下水均适于灌溉,合理灌溉不会造成盐害和碱害。  相似文献   

6.
城市化对地表水质的影响研究--以宝鸡市为例   总被引:3,自引:0,他引:3  
刘引鸽  宋军林 《水文》2005,25(2):20-23
城市化带来了诸多的城市环境问题,尤其是地表水质的恶化。采用1983-1999年宝鸡市地表水质监测资料及城市发展中有关的社会经济统计数据,采用ROSS评价指数方法,分析了宝鸡市区地表水质的时空变化特征及城市化对地表水质的影响。  相似文献   

7.
《地下水》2021,(2)
大沙河水库工程位于山东省菏泽市的单县,入库水源主要是黄河水。本文以黄河高村水文站为参证站,基于1950-2014年长系列水文资料,对大沙河水库引水条件进行分析,并对库区地表水和地下水水质进行评价,结果可知:水库取水河段来沙量、含沙量、冰凌和水质等引水条件均符合要求。大沙河水库入库前水质达到地表水Ⅲ类水标准,可作为生活饮用水和工农业用水水源,而库区附近浅层地下水水质较差。研究结果以期为区域水资源合理开发利用提供基础依据。  相似文献   

8.
通过资料汇总、现场调查、取样试验、类比分析等手段,对区域内冰川雪水、河流水、湖泊水等地表水资源分布特征、水质条件进行研究。该区域地表水资源主要以降雪或融雪补给为主,冰川雪水水质状况较好,河水水质状况相对较差,湖泊水水质状况最差。因生活需要,采用冰川雪水、河流水、湖泊水为饮用水源时,对冰川雪水可经简单净化处理后即可符合饮用水源条件,河流水与湖泊水则需根据实际情况加大净水措施。  相似文献   

9.
陈炎 《地下水》2018,(6):90-92
淮北平原位于安徽省北部,地处黄淮海平原南侧,地表水资源匮乏,地下水资源为主要供水水源。随着工业化、城市化水平不断提高,地下水环境问题尤为突出。本文以淮北平原2017年浅层地下水水质监测数据为依据,对该区域浅层地下水水质情况进行评价并分析水质变化原因。结果表明:该区域浅层地下水主要以Ⅳ、Ⅴ类水为主,Ⅲ类及以上水分布较少,浅层地下水水质状况较差,应继续加强淮北地区地下水资源监测工作,重视地下水污染防治工作,保证区域水资源安全,实现地下水资源可持续开发利用。  相似文献   

10.
张龙江  朱维斌  陶然  朱伟 《地下水》2006,28(5):44-46
本文通过对濉河符离集段地表水与傍河浅层地下水的水位、水质进行同步观测,采用相关分析的方法,对濉河符离集段地表水与傍河浅层地下水的水位、水质相互关系进行了分析.结果表明,地表水与地下水水位高度相关,傍河地下水水位与离河距离、河水水位关系表达式为:z=-5.9254-0.0003x 1.2110y,地表水与地下水水质的Cl-离子、NH3-N相关性良好.可见濉河地表水污染对傍河浅层地下水污染有着积极的影响.  相似文献   

11.
International unity is becoming ever stronger in this country owing to an increasing similarity in the development of the cultural environment. This comprises the provision of all the country's republics with a sufficient number of schools, theatres, and other institutions and cultural information media in accordance with the needs of the population. An important part is played by the rise in ‘the general educational level, as well as the level of professional qualifications and skills. Among all the Soviet nations and nationalities, this rise being more rapid among formerly backward peoples. Prominent among the factors of internationalization is the progressive development of the nationalities’ cultural resources, while professional culture is being increasingly brought within the reach of the masses.The implementation of the nationalities policy promotes the all-round development of all Soviet nations and nationalities, their drawing together, the upsurge of the individual capabilities of every Soviet citizen.  相似文献   

12.
The Global Stratotype Section and Point (GSSP) for the base of the Silurian System was defined in 1985. Since that time, a number of researchers have suggested that this section has serious deficiencies for use as a GSSP. As a result, in 2000, the Subcommission on Silurian Stratigraphy (SSS) proposed undertaking a formal restu@ of this GSSP, which was subsequently approved by the International Commission of Stratigraphy (ICS). The result of this restudy was the formal proposal that the current GSSP, at 1.6 m above the base of the Birkhill Shale, at Dob's Linn, Scotland, should be maintained as the same locality and stratigraphic level, but the bios- tratigraphical definition of the boundary should be revised. The previously defined, basal Silurian grapto- lite zone, the Parakidograptus acuminatus Zone, should be subdivided into a lower Akidograptus ascensus Zone and a higher E acuminatus Zone. The base of the A. ascensus Zone, marked by the first appearance of A. ascensus, should be regarded as the biostratigraphic mark for the base of the Silurian. This proposal has now been formally approved by the SSS and ICS, and ratified by International Union of Geological Sciences. This is the first GSSP to undergo formal restudy and redefini- tion, and the proposal also included a recommended procedure for restudy of GSSPs.  相似文献   

13.
It is known from observations that the center of mass of the Moon does not coincide with the geometric center of its figure, and the line connecting these two centers is not aligned with the direction toward the center of the Earth, instead deviating toward the Southeast. This stationary deviation of the axis of the inertia ellipsoid of the Moon to the South of the direction toward the Earth is analyzed. A system of five linear differential equations describing the physical libration of the Moon in latitude is considered, and these equations are derived using a new vector method taking into account perturbations from the Earth and partly from the Sun. The characteristic equation of this system is obtained, and all five oscillation frequencies are found. Special attention is paid to the fifth (zero) frequency, for which the solution of the latitude libration equations are stationary and represents a previously unknown additional motion of the rotational axis of theMoon in a cone with a small opening angle. In contrast to the astronomical precession of the Earth, the rotation of the angular-velocity vector is in the positive direction (counter-clockwise), with the period T 3 = 27.32 days. On this basis, this phenomenon has been named “quasi-precession.” This quasi-precession leads to a stationary inclination of the major axis of the inertia ellipsoid of theMoon to the South (for an observer on Earth), making it possible to explain one component of the observed deviation of the center of mass of the Moon from the direction toward the Earth. The opening angle of the quasiprecession cone is approximately 0.834″.  相似文献   

14.
Important tendencies in development of the world mineral-resources sector at the beginning of the 21st century were an increase in production and consumption of mineral materials differentiated by types of metals and nonmetallic mineral raw materials, by countries and regions, as well as the concentration of the production of mineral raw materials in a small number of countries, and a reduction in industrial reserves of minerals in the world economy, even at the current stage of their extraction. These tendencies should be taken into account in working out a strategy for development of the Russian mineral raw-material base.  相似文献   

15.
Taking the example of W Sudan, an analysis of the climatic incidents leading to the two recent famine disasters is made. On this natural background, the human side is investigated. Focus is directed towards the fragile economic structure of the famine-prone population groups. An early-warning system for famine in the Sahelian Zone is proposed taking grain production and storage, livestock development and the relationship between the prices of livestock and grain as major indicators.  相似文献   

16.
东濮凹陷北部沙三中亚段广泛发育盐岩和烃源岩,这两个看似不能共存的物质却在这里互层共生。该时期研究区沉积特征为多盐韵律与多层烃源岩互层共生、连续沉积,单个盐韵律厚度从几米到十几米,烃源岩有机质丰度高、类型好。平面上,两者在湖盆沉积沉降中心共生;垂向上,高有机质丰度、好干酪根类型与高盐度地层具有较好的对应关系。因而成为恢复古气候和古环境的重要研究对象。通过岩石学、古生物学以及Sr/Ba、B/Ga、(V+Ni+Mn)、Fe/Mn、Sr/Cu、Mg/Ca、V/(V+Ni)、稀土元素含量和氯同位素等方法对凹陷北部沙三中亚段的沉积环境进行研究。结果表明,凹陷北部沙三中亚段为深水沉积的还原环境,古盐度较高,达到半咸水-咸水沉积;微量元素和孢粉化石特征表明研究区沙三中亚段为温暖潮湿的环境。  相似文献   

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The structure of the eastern Pyrenees consists mainly of south-directed thrusts involving basement and cover rocks. An antiformal stack developed by the piling up of basement thrust sheets which outcrop in the Axial zone. These structures account for a thin-skinned thrust model rather than a vertical fault model in which the Axial zone would be essentially autochthonous, and the North-Pyrenean fault the axial plane of a fan thrust system. New data from the Eastern Pyrenees and the thin-skinned model suggest that(1) the structure east of the Pedraforca nappe is similar to that of the Central Pyrenees; (2) the cover rocks of the South-Pyrenean units and of the Axial zone-after restoration—built up a northwards-thickening prism consistent with the existence of a unique Pyrenean sedimentary basin during Mesozoic time; (3) the Axial zone is only a complex antiformal stack developed as a part of South-Pyrenean system related to the Paleogene thrusting-tectonics. The Axial zone palaeogeographic area had no special meaning during Mesozoic time.  相似文献   

20.
In order to characterise the influence of the heavyrains on the observed landslides during the 1996–1997hydrological cycle, rainfall records for the last 100years are analysed from 104 stations in easternAndalusia. Regarding the amounts of rain recordedbetween October 1996 and March 1997 in the 104stations studied, 31 presented new all-time records;15 presented values that were 80–100% of thepre-1995 record; 49 stations, 80–50%; and 9stations, < 50%. A map has been devised of thesusceptibility of the materials through which thesouth-eastern Andalusian road network crosses,together with an inventory of the damage caused byinstability phenomena on banks and cuttings of theroad network during the winter of 1996–1997. Therelationships between the rainfall during the studyperiod, the damage caused to the road network and thesusceptibility of the materials affected are analysed.The results indicate that there is a clearcorrespondence between the rainfall recorded and thesusceptibility of the materials with the inventorieddamage. It is concluded that the widespread seriousdamage caused in early 1997 to the roads andsurrounding areas in the Alpujarra region and thecoast of the Province of Granada was mainly caused bythe extraordinarily heavy rains. However, considerablyless damage was observed where the susceptibility ofthe terrain is low, thus highlighting the extremeusefulness of terrain-susceptibility maps for riskprevention and territorial planning.  相似文献   

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